Buggy code:
public class SignupDataFragment extends Fragment implements GoogleApiClient . ConnectionCallbacks , GoogleApiClient . OnConnectionFailedListener { private static final String TAG = "SignupDataFragment" ; public boolean viewReady = false ; public boolean bitmapReady = false ; public Bitmap profileBitmap ; Bundle userDataBundle ; View rootView ; private HashMap < String , String > input ; private SparseArray < EditText > editTextArray = new SparseArray ( ) ; private Button submitButton ; private ImageView profileImageView ; private GoogleApiClient mGoogleApiClient ; private Location currentUserLoc ; private Location approxUserLoc ; public SignupDataFragment ( ) { } public static SignupDataFragment newInstance ( Bundle bundle ) { } public static void goToMainActivity ( Activity act ) { } @ Override public void onStart ( ) { } @ Override public void onCreate ( Bundle savedInstanceState ) { } @ Override public View onCreateView ( LayoutInflater inflater , ViewGroup container , Bundle savedInstanceState ) { } private String getStringFromEditText ( int id ) { } private void setDataToFields ( int id , String fieldName ) { } private void autoFillData ( ) { } private void initializeEditTexts ( int id ) { } private void getInput ( ) { } private boolean validateInput ( ) { boolean f = true ; if ( input . get ( USER_NAME ) . isEmpty ( ) ) { Toast . makeText ( getActivity ( ) , getActivity ( ) . getString ( enter_name ) , LENGTH_LONG ) . show ( ) ; f = false ; } if ( input . get ( USER_PASSWORD ) . isEmpty ( ) ) { Toast . makeText ( getActivity ( ) , getActivity ( ) . getString ( enter_name ) , LENGTH_LONG ) . show ( ) ; f = false ; } if ( f && ( input . get ( USER_INSTITUTE ) . isEmpty ( ) ) ) { Toast . makeText ( getActivity ( ) , getActivity ( ) . getString ( enter_institute ) , LENGTH_LONG ) . show ( ) ; f = false ; } if ( f && ( input . get ( USER_EMAIL ) . isEmpty ( ) ) ) { Toast . makeText ( getActivity ( ) , getActivity ( ) . getString ( enter_email ) , LENGTH_LONG ) . show ( ) ; f = false ; } if ( f && ( input . get ( USER_QUALIFICATIONS ) . isEmpty ( ) ) ) { Toast . makeText ( getActivity ( ) , getString ( enter_qualifications ) , LENGTH_LONG ) . show ( ) ; f = false ; } <START_BUG> if ( f && ( isEmailValid ( input . get ( USER_EMAIL ) ) ) ) { <END_BUG> Toast . makeText ( getActivity ( ) , "Please<seq2seq4repair_space>enter<seq2seq4repair_space>a<seq2seq4repair_space>valid<seq2seq4repair_space>email<seq2seq4repair_space>id" , LENGTH_LONG ) . show ( ) ; f = false ; } if ( f && ( ( input . get ( USER_INTERESTS ) ) == null ) ) { input . remove ( USER_INTERESTS ) ; input . put ( USER_INTERESTS , getActivity ( ) . getString ( empty_interests ) ) ; } return f ; } private boolean isEmailValid ( String email ) { } private void startNextActivity ( ) { } private void pushInputToParse ( ) throws ParseException { } public void setProfilePicture ( ) { } @ Override public void onConnected ( Bundle bundle ) { } @ Override public void onConnectionSuspended ( int i ) { } @ Override public void onConnectionFailed ( ConnectionResult connectionResult ) { } protected synchronized void connectToGoogleApi ( ) { } private void startLocationService ( ) { } }

Fix:
if ( f && ( ! ( isEmailValid ( input . get ( USER_EMAIL ) ) ) ) ) {